Iron disilicide formation by Au–Si eutectic reaction on Si substrate

We have investigated the growth of iron disilicide on Au-coated Si(0 0 1) substrates and its photoluminescence behaviour. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy observations revealed that the Si surface above 380 °C was melted as a result of the Au–Si eutectic reaction and that coarse island disilicide grains with sizes of several micrometres were formed on the Si surface. The full width at half maximum of 0.056° on the rocking curve of α-FeSi2 004 was observed on the sample deposited at 800 °C, and indicated the high crystal quality in perfection of orientation. The photoluminescence spectrum of β-FeSi2 grains, which were deposited at 750 °C, was observed. The melted Si surface contributed to the improved crystallinity of α-FeSi2 and β-FeSi2.